In the chemical industry, particularly in the gasoline industry, problems of long standing exist in the centralized control of additives provided to main product flows. In the example of the gasoline industry, pipelines deliver gasoline from refineries to remote storage areas called terminals. The terminals have gasoline storage facilities and truck loading facilities. Usually each terminal has two or more lanes in multiples of two so that two or more delivery trucks may be simultaneously loaded with gasoline for delivery to retail stations. Each lane usually has three additive controllers for mixing additives into the loading pipes according to predetermined ratios of additives and gasoline. Heretofore additive controllers have used positive displacement pistons for injecting predetermined quantities of the additives to the gasoline. The additive controllers were periodically inspected by terminal personnel, who manually recorded readings and checked operations. The proper ratio of gasoline additiives to gasoline is dependent upon continued operation of reciprocating positive displacement additive controllers, and their inspection and observation by trained terminal personnel.
Problems continue to exist in the control and assuredness of operations and additive ratios, and in the immediate response to malfunctioning additive controllers.